JAL Rescheduled and Cancelled My Flights, Process and Reasonable Requests?

My partner and I have flights for Japan scheduled in December - January, have been waiting for a border change and are now very excited that it seems to be happening.
A few days after tentative announcements about visas and requirements being dropped JAL emails us the following:

1. An email about our outbound Business class flight being rescheduled to a flight 32 hours later
2. An email stating our seats have been changed on outbound flight
3. An email stating our return Economy flight has been cancelled - no mention of refund; offers of possible reschedule
4. An email stating the days they are having flights and ones they are not

They advised they will call customers affected in 'order', we are assuming it will be a wait due to the timeframe of us flying.
Cannot confirm the reschedule as their website recognises the changes in our bookings and is unaccessible, a call will be necessary.

The email with the days they have flights confirmed our original outbound flight is still occurring, our return flight doesn't exist so we will need a new flight and have to be back by a certain date due to government work timeframes. (Despite them still selling tickets to our return flight on their website…)

I'd like to call them sooner rather than waiting for their call later, concerned that what little return seats are left will be snapped up.
On their website for 'reservation changes' it states "If the change results in extra costs in fare, charges, taxes, or miles above the purchase price, you do not have to pay the difference."

If I call and request a reschedule for the cancelled flight, are they expected to provide one?
Anyone else enjoyed JAL wait times so I can be prepared for how much of my day I'll be on hold?
Could I be a 'Karen' and try and get put back on my original flight as they have informed me in writing it is still occurring?

Any help would be wonderful, was mentally prepared to have to cancel the whole trip with the border rules in August. Despite this stress looking forward to getting to enjoy the trip I've been dreaming of for years!