I've made an Brown IPA with both London and 1056 and both turned out awesome! I've never used Maple Syrup but I would assume it can be used like Honey. Either add it at flame out, high krausen or prime with it. Be aware it is probably close to 100 % fermentable so it may dry and thin out the beer. You might want to add 4-8 oz of malto-dextrine to the recipe to add back some body