Much of the language of Paul's epistles is rooted in the subsoil of covenant. Being a Hebrew of the Hebrews and a Pharisee beyond reproach [Phil 3:5] the framework of his writings is grounded firmly in the redemptive workings of a covenant keeping God. Paul's first-century audience would have had less difficulty in grasping the "covenantal nature" of his words than the modern penchant for literalness.
Paul's use of 'body' in 2Cor 5 has nothing to do with an individual's personal status after death – then or now, but everything to do with that 'corporate body' of the old covenant Israel from which the first-fruit believers in the "this generation" [Mt 24:34] were in the process of coming out of. Theirs was a resurrection like unto Christ's – a coming up out of from among the dead [Act 26:23; Rev 1:5] i.e., out of old covenant Israel. They, the first-fruits 'body' of believers were the new, restored or "raised" Israel [Ezek 37:1-14], being refashioned in the likeness of their master; they were the first-fruits of and thus ON BEHALF OF the whole harvest – the whole harvest being historic Israel of the Old Covenant. Israel's redemption came through Christ THE first-fruit and was duly administered through His first-fruits elect [2Cor 5:19-20]; this, in turn, wrought the reconciliation of the whole world – Israel was the means to this ends, i.e., the restoration of humanity to God. This was the outworking of Christ's victory established through the Cross.
Paul using clear Old Covenant language said:
2Cor 5:4 For we that are in this tabernacle do groan, being burdened: not for that we would be unclothed, but clothed upon, that mortality might be swallowed up of life.
Paul's mortality or fleshliness was in relation to that of the limitations of the Old Covenant in regards to receiving the promised redemption – that in which they were in transition from, to the full life of redemption in the New Covenant through Christ. Jesus was one born under the Old Covenant to redeem those of the Old Covenant to bring them from child-hood to "son-ship" [Gal 4:1-4]. He died in and to the body of the Old Covenant, and so fulfilled its requirements – that was the "body" of which Paul speaks. Note, the Greek tense is singular – not plural "bodies". cf., Phil 3:21; Rom 8:23 on the redemption of our [plural] body [singular] i.e., the corporate body. It is the same language, therefore same understanding i.e., covenantal transition that Paul uses in being delivered up and dying daily – out of the old and into the new. And particularly on behalf of those to whom he writes, hence what is "working death in us" means "life in you" [2Cor 4:12]. In no way is any of Paul's language speaking of literal individual fleshly [of whatever nature] bodies post death.
Not only that, but the Greek tense of absent and present in 2Cor 5:8 are both aorist infinitive – meaning actions as having occurred with ongoing results i.e., it was a then process and NOT something that was to occur later upon or beyond physical death.
Further… Paul's statement: "Therefore we also have as our ambition, whether at home or absent, to be pleasing to Him" 2Cor 5:9 shows this understanding of the 'corporate body' image. It makes no sense at all supposedly being at home "in heaven" in a "glorified fleshly" body [never actually stated], trying "to be pleasing to Him" or as the KJV has it "accepted" – what? is there still more to do after death to be accepted and found pleasing to Him? This makes no logical or biblical sense at all. Their being "at home" or "absence" [from the body] was the continual putting off and putting on of the old/new natures [covenants] respectively progressively. They were in the process in that transitional generation of moving out of one glorious House [covenant] – whose splendour was fading and ready to crumble [Heb 8:13], into another more glorious House [covenant] – built without hands, complete and glorious in the heavens [2Cor 3:7-11]. It is all covenantal language [2Cor 5:1] – the House of Moses was being replaced by the House of Christ – the covenant of Law being replaced by the covenant of Grace:
Heb 3:5-6 And Moses indeed was faithful in all His house as a servant, for a testimony of those things which would be spoken afterward, but Christ as a Son over His own house, whose house we are if we hold fast the confidence and the rejoicing of the hope firm to the end. [The writer of course speaking to the then perseverance of the elect]
Thus their walk was in the likeness of Christ's faith, not according to fleshly ordinances i.e., they were to walk by New Covenant faith and not by Old Covenant sight. The Old Covenant was natural, corruptible, dying and ready to pass away, but the New Covenant – spiritual, incorruptible and full to life.
For Paul 'the body' was one entity, that is, historic Israel – just having two modes or worlds of existence in that transitional time period AD30-70. The first mode was that of the Old Covenant world i.e., Law-works. The second mode was the New Covenant i.e., Grace-faith. As one was being "cast out" [Gal 4:30] the other was being "put on" [Eph 4:22-24]. Resurrection was about the finality of the transformation of that one entity, Israel – that's why Paul in relation to the body uses the singular descriptive word IT:
1Cor 15:42-44 So also is the resurrection of the dead. The body is sown in corruption [old covenant], it is raised in incorruption [new covenant]. It is sown in dishonor [old covenant], it is raised in glory [new covenant]. It is sown in weakness [old covenant], it is raised in power [new covenant]. It is sown a natural body [old covenant], it is raised a spiritual body [new covenant]. There is a natural body [old covenant], and there is a spiritual body [new covenant].
Further textual proof of this is found in parsing the Greek: each "it is sown … it is raised" is in the present tense, thus literally reading "it is being sown … it is being raised" – actions that were ongoing and continuous in that age, and not beyond the grave i.e., the old Mosaic life was being put off as the new covenant life in Christ was being put on [Eph 4:22-24; Col 3:5, 8-10; Rom 6:4; 7:6; 8:13].
In this passage there is NOT two distinct separate "bodies" as such, but rather the one body in transition. The natural body answers to the old covenant world that was passing, the spiritual body answers to the burgeoning new covenant life – "IT" was the one body in transition – death, embodied in the old covenant was being swallowed up in new covenant life [Isa 25:8; 1Cor 15:54-57]. IT was the redemption corporately of historic Israel and thus, in consequence, the reconciliation of the whole world. Israel was the divinely appointed means to this end – in Christ and the first-fruit saints this has been fulfilled.