I'm taking the server down for most of the day tomorrow, Monday daytime is always very quiet with 1-3 players most of the time so the impact should be minimal.
I will be taking it down around 8am UK time and estimate it will be back online by 4-5pm, this is to clear out a significant amount of data and test for issues relating to the hosting company switch.
If everything goes to plan this could mean that we will be switching before the 26th, so keep your fingers crossed!