Hi, I have already developed a project using the Microchip WINC1500 module. you can see more about that project here:
https://www.freelancer.com/projects/c-programming/adding-WIFI-capability-PIC/details
In that project I used the WINC1500 in Ethernet mode, that is, the TCP IP Stack run on the main controller ( an PIC32MZ2048 series ), not on the WINC Module itself.
I have neither worked yet on the ATSAM series of controllers, nor with the AWS services, but this makes this project all the more interesting to me in order to learn a new development environment.
I already have the demo board:
SAMD21 Xplained Pro + WINC1500 Xplained Pro Extension board + I/O1 Xplained Pro Extension board
Which, although with a different processor, could be used to start some tests. And I would have no problem to try to acquire the SAML21 series processor which you mentioned.
Another issue is that I would not be able to work full time on this project, so I would need some "flexibility" on the timeline.
If you think I can be of help with your project, please let me know, I would be very glad to discuss more details, and even do some preliminary work before you assign the project to me, so you could see how I work and then decide.