Deployment of the latest update begins at 17:30 GMT. We're aiming to be done in time for any races starting at 18:00 GMT.
Any races starting between 17:00 and 18:00 will experience delays of up to 30 minutes. Hosts of the affected leagues will be contacted with the option to postpone their race(s) should they wish.
Read more about the update here:
http://www.igpmanager.com/news-article/43/igp-manager-is-announcing-a-significant-development-upgrade