I run ultramarathon distances and am confident most of the foods I use would bode well for your usage, as well. Dates work well for me, though I do prefer them to be relatively fresh, or at least reconstituted with water. I do recommend testing, while biking, what digest well for you. Soaking dates, and using the date/sugar water is another option instead of coconut water and may carry higher calories.
Can you plan ahead and set up a custom bag or two at various stations?
Is sodium a concern for you? Have you steered clear of salt for at least 10-12 weeks?
Also, Harley "durianrider" (search 'durianriders' on youtube), is a premier cyclist on a 80/10/10 diet. I am sure if you peruse his videos that he must talk about how he fuels for long races (He has won 24 hour races).