point to /vehicles and to MDS / GBFS guidance document

Author: thekaveman

provider/README.md

@@ -354,7 +354,9 @@ Without an `event_time` query parameter, `/status_changes` shall return a `400 B
 
 ### GBFS
 
-All MDS compatible `provider` APIs must expose a public [GBFS](https://github.com/NABSA/gbfs) feed as well. Compatibility with [GBFS 2.0](https://github.com/NABSA/gbfs/blob/v2.0/gbfs.md) or greater is advised due to privacy concerns and support for micromobility. 
+All MDS compatible `provider` APIs must expose a public [GBFS](https://github.com/NABSA/gbfs) feed as well. Compatibility with [GBFS 2.0](https://github.com/NABSA/gbfs/blob/v2.0/gbfs.md) or greater is advised due to privacy concerns and support for micromobility.
+
+GBFS 2.0 includes some changes that may make it less useful for regulatory purposes (specifically, the automatic rotation of vehicle IDs). The [`/vehicles`](#vehicles) endpoint offers an alternative to GBFS that may more effectively meet the use cases of regulators. Additional information on MDS and GBFS can be found in this [guidance document](https://github.com/openmobilityfoundation/governance/blob/master/technical/GBFS_and_MDS.md).
 
 ### Events