Buy Grail cf slx with Shimano RD-RX815 Di2 or wait for the new Shimano RX825 Di2 Product Release?

Yo,

Where's the sale for the Grail CF SLX with Shimano RD-RX815 Di2? Canyon's gonna release the Grail with the new Shimano RX825 Di2 soon, just like they did with the Grizl. Should I wait and pay an extra 1000-1200 euros for the new Shimano RX825 Di2, or should I save some money and get the RD-RX815 Di2?

Is there a big difference between rx815?

https://www.canyon.com/en-lt/gravel-bikes/performance/grail/cf-slx/grail-cf-slx-8-di2/3579.html?dwvar_3579_pv_rahmenfarbe=R120_P02