I e-mailled them a couple weeks ago before the site overhaul and they replied with:

The Repressor was taken off sale as we needed to carry out extensive re-mastering work on the kit. Periodically master models need some work so we can continue to produce moulds, this means we have to take the products of sale for a short time to replace and repair the master models and then produce new moulds. The amount of time this takes depends on many factors including the level of detail in the model and the level of work the designers and mould makers already have scheduled. Unfortunately this means we can not give an accurate estimate of how long they will be unavailable for."