Relentless Assault additional combat phase is summoning sickness over by then? magic

[gaminger]

if I play Relentless Assault and I get the 2nd main phase and combat phase, do creatures I summoned that turn still have summoning sickness in that additional main phases and combat phases? because its almost like a second turn so does the summoning sickness wear off?

[Void Elemental]

Creatures have summoning sickness unless you had them under your control since the beginning of your current turn.