The was looking at is this one ...
Stoppage: Grand Union Leicester Line Kibworth Top Lock 18 - Kings Lock 38
02 Apr 2012 until further notice
Associated Regional Office: South East Waterways
From Monday 2nd April to Friday 13th April navigation will be open 10.00am - 4.00pm daily.
From Friday 13th April at 4.00pm, navigation between Kibworth Top Lock 18 and Kings Lock 38 will be closed to navigation due to water availability in the area.
Locks 18, 30 and 38 will be padlocked to avoid abuse.
Weekend openings will be considered based on available water supplies as the season progresses and if possible, this will be communicated at a later date.
I guess that's not technically Foxton which is Locks 8-17 ... but effectively means the same thing for my trip and I need to go somewhere else.