The other being keeping hot rocks in the chalk bag (if there are enough shakeouts on the route),
for alpine rock routes and grit bouldering, I managed best by letting my hands get really cold, go through hot aches and keep my core and arms warm - numb out the fingers whilst not getting pumped or tired and then get the heart rate up jumping about and doing pressupsno experience on UK limestone in the cold(ish)
You want one of those heated velodrome suits an a bike on rollers for between redpoints.
Another route at Wimberry, again around f8a+/b. Probably an even colder day. Route climbed very much like a sport climb, couple of little chalk ups but not really shake outs. Not so serious so had a proper run around (15-20 mins) and came back to the route really warm, jacket off etc. Put jacket + hat on to tie in and do boots. No cold hands on route, not even a little.
You want to get yourself one of those easyjet tickets to spain.
Kentucky followed by Antalya Spain, that should do?
I will be looking at USB and lighter-fluid based options for the upcoming winter season (and some mitts).