My hearing fluctuates often and quite a bit - 40 -50 decibels in some frequencies. I’d like to have at least 3-4 different programs based on different hearing tests (worst day, best day, and a couple in between) I am testing Phonak Sphere i90’s right now and they say I can only have one main program. If they create another program, then none of the AI, or automatic features will work when I’m using that program. Anyone have any experience with this? Or have any suggestions for hearing aids that accomodate fluctuating hearing?? Help! 
Just to give you some comfort the short answer is yes.
Some users create a manual program to force Spheric mode on demand rather than have to wait for the auto Parameters to cut in.
Others will be along to give you more details.
You are going to have an embarrassing moment with your audiologist.
You could be considering diy.
Sorry you haven’t had any other responses. I think the title may have confused others.
Depending on the level of aids you have you can usually create up to four manual programs based on a choice of other installed programs.
To create what you are asking you would have to do several hearing tests at those times when you suspect the variations were present.
You would have to then enter those gain values and other settings into the created manual programs.
Obviously not the usual time Dependent action of someone telling you it can’t be done.
That is why I suggested you research diy.
Lets ask @firenzel for his expertise.
consider DIY buddy. I’m in the same situation. I don’t have the hearing aids yet, but I do know what I want to buy. My main advantage may be that I’m a sound engineer so I have some knowledge about what those settings mean, but we all have the internet. I suggest you reading a lot about the physics of sound, understand what’s a dB, what’s frequency, how the proprietary software for your hearing aid works and so on. On the other hand 10dB fluctuation in all frequencies a day is not a great what. Most of the hearing aids you see sold have some basic eq like: treble bass middle… they let you play with 5dB plus or minus. Welll I think it suffice. Keep in mind for a perfect DIY setting you should be able to measure hearing, make audiograms so you know for sure what’s lower and higher. Such devices are very expensive. I wanted to buy for myself some Senheisers used in audiometry and they where like 500 USD… god forbid. Also you need a pure sine generator (hardware preferably) and the most important the calibration. This is the most hard thing. You don’t have the technical capabilities and to invest thousands of dollars (or Euro or whatever) in such toys makes no sense. I do encourage you to study about the sound and how to play with your hearing aids.