See its up to you if you want to add more honey. In theory you can keep adding further honey until the yeast poops out.
I'd be wanting to work out why the start gravity was so low. 15lb made up to 5 gallons or so should have given a gravity in the 1.100 to 1.110 area. If it was just not very well mixed then there may still be a layer of honey at the bottom and just taking out the bag of fruit and giving a damned good stir would remedy that.
Just blindly adding honey until the yeast poops out could leave you with a very sweet mead.
You could have just mis-read the hydrometer or a little fruit pulp might have helped give an incorrect reading etc.
If you just want to get it finished you can just keep step feeding, then once the yeast stop fermenting and you get a consistent gravity, you can just remove the fruit, give it a damn good stir, then retest.
If it did turn out to be too sweet because of unmixed honey, you can just fortify it with a litre or two of bourbon, then clear it and either bottle or bulk age......
As an aside. You seem to be in Miami, so you need to read up on your ingredients a bit rather just relying on recipes. Why? Because D47 isn't a yeast that likes warm temperature. It prefers 70F/21C max or it stresses and can make fusels that take a long time to mellow. A lot of mazers in warmer areas find this a pain so either use temp control of some sort or a more temp tolerant yeast......