Just download the files needed for rollback:
Rollback WW 2.13B Android 8.1 April 2018:
WW 2.13B>WW 2.22A May 2018
WW 2.22A>WW 2.22A SP01 June 2018
WW 2.22A SP01>WW 2.22A SP02 July 2018:
I sideloaded the above files, however i still get an ota for v2.13B April. Any fixes yet ?