On balance it makes more sense to use them up because of the interest they will give you meanwhile.    I don't know exactly the yield in terms of spins you might get returned but even if it was only 1 or 2 spins per day extra you might as well take it I think.    My guess is FBC never foresaw people on purpose saving spins, I do it myself sometimes but Im not feeling it presently.
  Also sideways for BTC is in effect bullish, Im biased to this view because hard wired into my brain is all the years BTC was in the hundreds.  We languished all the way back down to 200 still seems like yesterday even though its over 5 years now but  I can see it still in the rear view mirror and us being well past 20k like this is like cloud heaven bound imo.   BTC is cruising like Concorde at this altitude and just holding even if boring is still record breaking performance to me, we seemingly can rise from here and in time it appears possible.
  I wouldn't especially wait for negative BTC action not in the long term, momentary spikes sure of course it can occur its only a case of order books being flushed out to move a price I guess.   But the opposing view of Dollar becoming a 'hard currency' making headway vs BTC is not happening, even with these higher rates its below inflation.   It'll always be that rates are below inflation the dollar is always losing value I dont see how they would dare (or able) to change policy from what they've done for over ten years now.  Macro view BTC is fine hence if anything I think we rise or have that bias now that 2022 trend is over.