The sweet spot temp for D47 is between 59 and 68, so your current fermentation temp of 60 is good. I've heard anything over 70 definitely produces a noticeable undesirable taste. So while your mead is fermenting your temp should remain within this range.
That being said, I believe that if you've provided your yeast "5 Star" accommodations from the beginning (i.e. SNA, rehydration, temp control, pH, etc.) they should be more tolerant of less than stellar accommodations later on in the ferment when the uptake of nutrients is significantly reduced. So if you rack at SG 1.02 in ambient temperature for example, you should be ok. As long as your ambient temp isn't 75 or 80, you know?
D47 alcohol tolerance is about 14%, sometimes more, depending on how happy your yeast is. That's a starting gravity of at least 1.106, assuming your ferment goes dry to 1.000. If you use more honey it may never get to 1.000, so it's good to know your yeast tolerance so you can plan before the ferment and know what to expect during and after the ferment.
My target is always 1.000, but never beyond 3 weeks, but I'm just being cautious, especially if I have fruit in the primary. I haven't heard that lees from D47 produce a bad taste if you don't rack for a long time. 71B I heard was bad if left beyond a couple weeks.
