Will ASA automatically pick up an HSRP priority change

[CiscoMedMed]

I'm in a temporary configuration with two Nexus VPC switch pairs serving the inside network of my ASA 5525. 

Call the switch NX01 02 03 04. NX01 02 are a VPC pair and 03 04 are a pair. There are four real addresses and one HSRP VIP - say VIP 10.100.100.1, real addrs 10.100.100.2, .3, .4, .5. Presently NX01 10.100.100.2 is active and has the VIP 10.100.100.1 and NX02 10.100.100.3 is standby. NX03 and 04 are listening. 

I want to make NX03 the active HSRP device and this should easily be done by raising it's priority above that of NX01 (and then raise NX04 to be greater than NX02). My concern is that the ASA will have any lapse in being able to reach the inside gateway 10.100.100.1 as I change to higher priority on NX03. I don't have a lab to test out how quickly everything will settle out for the ASA and the new owner or the virtual mac/IP pair. This particular junction point is where all Internet traffic flows through. Should changing the HSRP priority as described be seamless for the ASA?

[Marvin Rhoads · Accepted solution]

It should be seamless. When a device become the Active HSRP member it sends out a gratuitous ARP message to onform all adjacent devices (e.g., your ASA) that it now has the VIP address.

Reference: https://www.cisco.com/c/en/us/support/docs/ip/hot-standby-router-protocol-hsrp/10583-62.html

[CiscoMedMed]

Gratuitous arp for the win! Thank you.