Rebooking options when F is no longer available on the route?
A bit of a strange question. I had a First class booking MAN-FRA-DEL-ZRH-MAN for November this year, out with LH and back on LX. Lufthansa/Swiss have cancelled the booking and as per the COVID rules, I can rebook free of charge to a different date till end of December 2021, if I keep the same route. I am planning to potentially rebook for October 2021 but was told that I need to ring in November 2020 to rebook based on when the flights are released.
However it looks like LH have changed the aircraft on the FRA-DEL route from the 748i with F to an A343 with no F. If that is the case, what are my options without paying extra to stay in F and not downgrade to J?
I think the options are
1. The put me on LX which seems to still be flying to DEL via ZRH (is this considered a re-route or not since the final destination is the same?)
2. They let me change my destination for free from FRA to somewhere like BKK which still seems to have F?
I am suspecting that it is more likely option 1 but was interested in people's thoughts before I contact LH again for re-ticketing.