SWI and Legato

Hi All,
I am trying to determine the relationship between SWI versions and Legato versions for various AirPrime modules. We are currently targeting the WP7609 and the WP7610 as the first modules that we plan on supporting for our customers. I have been building my app with 2 different profiles, one for each modem. Specifically, I am using swi-wp76_4.7.0 (SDK for WP76 (Release 13.3 + Legato 20.04.0)) for my build on the WP7609 modem, and I am using swi-wp76_4.3.1 (SDK for WP76 (Release 13.2 + Legato 19.07.1)) for the WP7610 modem.
My impression is that Legato 19.07.1 is the latest version supported for the SWI version 13.2, while 20.04.0 is the latest for SWI version 13.3. I am using this matrix (https://source.sierrawireless.com/resources/airprime/software/wp76xx/wp76xx-firmware-latest-release/#sthash.X8MfSnbl.D32TiePm.dpbs) to determine which SWI release I need to use for my modem. From this resource, it appears that the WP7610 is supported up to 13.2, while the WP7609 is supported in 13.3.
That being said, I have accidentally applied SWI 13.3 + Legato 20.04.0 to my WP7610, and it appears to be working. I have also built my app using Legato version 19.07.1, and the legato tools crash on me with the following:
fwupdate@0: symbol lookup error: /legato/apps/e52c9c52573a8d363be326d7ab9e170f/read-only/bin/…/lib/libComponent_fwupdate.so: undefined symbol: le_thread_Sleep

Is my assumption that the WP7610 only supports SWI 13.2, and the WP7609 supports 13.3 correct? Based on this, is my assumption that the WP7610 only supports Legato 19.07.1, and the WP7609 supports Legato 20.04.0 correct?

Thanks,
Chris

“I have accidentally applied SWI 13.3 + Legato 20.04.0 to my WP7610, and it appears to be working. I have also built my app using Legato version 19.07.1, and the legato tools crash”

You should build the app with the version exactly equal to that in module.