At this point, it appears that the entire landscape is changed and that it's going to take a while for things to sort out.
Until this off season (and possibly last year if Nylander is enough evidence), it was pretty standard to lock up your top UFAs to 6 year deals prior to the last season of their ELCs. MacKinnon, Hall, Skinner, etc., etc. almost all were on 6 year deals.
While I think that locking up top RFAs coming off their ELCs to 8 year deals is rational because a player is going to generally be more productive in his late 20s than in his mid to late 30s, there has to be a lot of discretion on this. 8 years is a huge time commitment and with the number of contracts having the last few seasons very bonus heavy, these deals become essentially buyout proof.
As far as your list goes, I'd agree with locking up 4 of the 5 to long term deals. I'd go 6-8 years on PLD and probably the same on Jones-it's a few years to go before he's due so I'd reassess when appropriate. Anderson I'd go 5-6 years and ZW probably 6.
I'm not sold on a long term Bjorkstrand commitment yet.
As far as the exact time frame, I don't have any opinion. Case by case approach would seem to be the best strategy to me instead of getting locked into a particular date.
In any case, Jarmo had best get up to speed on RFAs. His previous strategy of 'using his CBA leverage' was an incoherent and ineffective approach. Other than the Jones steal, he's probably got as poor a record dealing with RFAs as any GM during a similar time frame. I'm not very confident that he'll make the necessary adjustments to the new RFA market. I know that will shock many here.