I must second Luis’ comments: this thread has been invaluable for me, not only in warning about the discontinuation, but especially in guiding readers to alternative sellers and, more recently, alternative options such as the Excel vacuum pumps.
I too received that dreaded e-mail from Lee Valley saying my order for the Vac-Sys System Set had been canceled (I have not heard that about my order for the Festool pump, still showing as backordered to 2/22/22).
I have ordered pieces of the system in anticipation of the unavailability of the System Set: I have an SE-1 clamping module; an extra round head; a foot pedal; and the accessory head set.
Last night after reading the last few posts, I ordered an SE-2 clamping module from Acme Tools.
If I don’t get the pump from Lee Valley—and perhaps even if I do—I plan to talk to Joe at Veneer Supplies about the Excel pumps and needed hoses and connections; perhaps even order a set of Podz.