1 Cor 15:20 “Now however Christ has been raised from the dead, the first-fruits of those who have fallen asleep.”

The analogy with falling asleep is supposed to be maintained, “resurrection/awakening” is a direct reversal of it.

Both are in the passive voice in the verse, but if Paul still allows for christ to be an active participant in his own death, there is also allowance for him to be an active participant in his own re-awakening.

Yes reawakened in the body, but the body itself is transformed into a spiritual/imperishable/heavenly one.

The living will have their bodies transformed in just the same way at the trumpet call – same as the dead who will be resurrected to the same body but a transformed one.

Yes a transformation – but the same body transformed.

Just as the seed that becomes wheat isn’t left behind but becomes the plant.

The point is that Paul believed the body rose and left the tomb (transformed though it may have been).