Although not really documented very well, /timers is for the active connection, so /timers off is going to only affect the active connection. I'd use the /timer* off method that was suggested as that's a good way to cover everything. In case you are wondering why that's not documented, it kind of is... /timertest off will turn off a timer with the name of test. Because * is a wildcard meaning everything, /timer* off would turn everything off.
