Marantz 8802 Vs 8802A As PrePro

Hello All, 

Considering an upgrade to my home theater preamp and looking at Marantz 8802 or 8802A Pre/pro. My setup is 4K TV and do 5.1 or 7.1 Surround. Sources are Apple TV 4K and Fire Stick 4k. 

Could you please advise what are the differences between 8802 & 8802A ? What would I wont be able to do if I go with 8802 ?

Thanks in advance for the help. 

The 7700 series is also worth taking a look at.  I went from an AV8801 to the AV7704 when I got my 4K TV and there was no noticeable difference in sound quality or picture quality and the AV7704 has all the connections I need.

If you're open to refurbished, I'd recommend taking a look at accessories4less.  You can get either the 7705 or 8805 with a 3 year warranty for way below retail price for a new one.
I had an 8802A and upgraded to a Lyngdorf M-60.
8802A is great but at this point in the model cycle, I'd probably move up to the 8805 as another poster suggested.