Would prefer to use something like Sika Pro which is a urethane rather than a silicone.
Did a lot of testing on sealing products when I worked in the commercial window industry and we settled on the Sika Pro as the best for that application.
It is an acrylic eurolastic coating that seals the roof and protects from UV wx etc. similar to Plas T Cote and Thermo shield but superior I am advised. I have contacted Sika who stated that 560 would be suitable for the requirement. Bloody expensive though at $222 for 15 lts with a 3 coat coverage of 3.1lts per sq m for 3 coats. Surely beingva Sika product it has to be good?