Should I change the week of my trip?

[Drogba11CFC]

I had planned a trip to the South West from 15th to 18th May but there is now an ASLEF overtime ban that week. I had considered moving it to the following week, however the RMT reballot closes on 4th May and I'm not sure whether they'll announce further strikes straight away, wait until after their strike on 13th May, or if they'll wait while they're counting the ballot papers (and if so, how long should it take?)

I will be predominantly travelling on the main lines (Paignton on Monday, Minehead on Tuesday, Weymouth to Alton on Thursday) with the exception of the Minehead to Weymouth leg on Wednesday.