I would be horrified to loose access to HRT - I hope you have good reasons and can be ok with it.
The effects of loosing HRT without having had SRS will of course be that T increases and E decreases, it will affect your body shape, facial features, breasts, skin, hair, muscles, fat,.etc
It would only affect your voice if your voice was not already affected to the maximum before the surgery. Since you had a VFS , I assume your voice was fully changed because of T before already. VFS does not reverse the effects of T, it just sort of puts a patch on it - so more T will not do any irreversible harm. The vocal chords already have their maximum length, so that will not change. However if you have been on hormones for a long time or if you also too Spiro, there may be minor changes in your voice due to changed mass of the vocal chords, mainly due to water retention and maybe muscle changes. Those should be reversible though when you get access to HRT again.