Priority Club and Amtrak Guest Rewards are transfer partners via Points.com. Once you have signed up for Points.com account, you can then link number of your accounts and perform transfers between them, often at very unfavorable rates. But it is worthwhile sometimes to clean up old accounts or for meeting some promotional activity requirements.
Now, you can transfer Priority Club points to Amtrak Guest Rewards points at very favorable ratio, however. You 3 Priority Club points will turn to 4 Amtrak Guest Rewards points. The minimum number of points that you need to transfer from Priority Club is 10000 but there doesn’t appear to be upper limit and you can transfer any amount over 10K.
Amtrak Guest Rewards Points for Hyatt Gift Cards and SPG Cat 1 to 4 Hotels
Guest Rewards members can redeem 10K points for $100 Hyatt gift card that is valid in United States, Canada and the Caribbean. So, 7518 Priority Club points gets you a $100 Hyatt gift card.