Get-out using spin chain thru to a right and left grand

Spin chain thru is equivalent to ends circulate; trade.

From a right handed wave with boys on the outside, girls and boys both in sequence.

If the (primary or secondary) boy who is facing in and his partner are in different waves, call (all 8) circulate.

If partners are together, call spin chain thru, girls circulate (once).

Otherwise call spin chain thru, girls double circulate.

You now have your partner by the right hand, girls on the ends, so you are facing in the correct direction for right and left grans; etc.

Weak floors may need a "rear back", but if everyone is moving at a relatively standard pace, you can call right and left grand before the dancers have taken the hand hold.  You might even get away with weave the ring.