The pre-order reservations for Steam Deck are running into availability problems it seems, meaning we can officially add the Steam Deck to the list of gaming hardware you'd love to buy, but just can't. Unfortunately, future availability is also looking rather vague right now, with sometime after "Q2 2022" the only timeframe Valve are giving right now as to when you'll next be able to get your hands on one.
Previously, Valve was giving specific periods for availability when making a reservation, however, the timeframe is now completely open-ended, and could be any time after that date. Customers in both the US and UK have noted the change, and it seems to primarily be affecting the more affordable versions of the hardware as of right now. - but as it stands - if you pre-order today, when you'll actually get it is a bit of a dice-roll.
Q3 2022? Q4? 2023? There's no real way to know. The only saving grace is if you're willing to pony up the extra cash to get the higher-end 512GB model, you'll still be guaranteed to get one sometime in Q2 2022. The dates seem to be shifting all the time, though, and Valve is no doubt adjusting both their dates and their production run plans, according to the demand.
There's no doubt though that Valve is starting to run into supply and demand issues when it comes to silicon, as are most hardware manufacturers right now. The device relies on AMD processors to power it, and the availability of those can be hard to predict. It seems that future supply projection is becoming more heavily tied into the global silicon shortages right now.