The new rules say that smaller (whatever 'smaller' means) stadiums can have 4000 spectators or 50 % capacity, whichever is lower. Larger stadium can have 10000 spectators or 25 % capacity, whichever is lower. Not sure what rules Lincoln are working to as it seems to be a mixture of the 2.
Maybe shutting one of their stands make them a smaller stadium (with a capacity of 6290) which means they can have a bigger attendance than a larger stadium with 10,653 capacity. Absolutely madness if that is the case.