I stopped at 59 and 95% out of fear that reaching level 60 would be the cutoff for RAF. I didn't want to boost all the way to 60 and learn the hard way that crossing the line to 60 made granting unavailable. /shrug

Regarding hub & spoke, the difference of level 30 vs 31 amounts to roughly 15-20 min of boosting. I had considered this as well, but the cost of the transfers being double the cost of an extra account over the RAF period was my reason for suggesting the method above. It isnt as fast, but less expensive and much easier to manage/keep track of.