Bottle cond. time to temp ratio!

I cant physically get any higher bottle conditioning temps that 66. On average most days, beer sits around 62-64.
Its been conditioning for 3 weeks now, but how much more time over a month would you add to conditioning when its 5-7 degrees lower than 70?

As long as it's within the temperature range the yeast works well in (not too low for it) you should good to start checking after 4-5 weeks. Chill one bottle for 5-7 days, then pour to glass.

I would suggest keeping track of the temperature (or temperature range) it was bottle carbonating at, for each batch (or at least each yeast strain) so that you can build up a database of this. After a while, you'll either find a general good starting point, or know for specific ABV ranges, yeast strains, and temperature ranges, what works.

There really are too many variables at play to ever give anyone a definitive answer. Carbonation is foolproof, if you added the right amount of sugar, the beer will carb...WHEN IT'S READY and not a moment sooner.

Temp and gravity are the two biggest factors. But there's no answer we can give you. All we can suggest is that after three weeks you try one every couple weeks til they're ready.