Update expressroute-howto-coexist-resource-manager.md

Correcting steps language as per point 4 in "Limits and limitations" in the same page.

Author: arunjvs

articles/expressroute/expressroute-howto-coexist-resource-manager.md

@@ -68,7 +68,7 @@ There are two different sets of procedures to choose from. The configuration pro
     If you don’t already have a virtual network, this procedure walks you through creating a new virtual network using Resource Manager deployment model and creating new ExpressRoute and Site-to-Site VPN connections. To configure a virtual network, follow the steps in [To create a new virtual network and coexisting connections](#new).
 * I already have a Resource Manager deployment model VNet.
 
-    You may already have a virtual network in place with an existing Site-to-Site VPN connection or ExpressRoute connection. In this scenario if the gateway subnet mask is /28 or smaller (/28, /29, etc.), you have to delete the existing gateway. The [To configure coexisting connections for an already existing VNet](#add) section walks you through deleting the gateway, and then creating new ExpressRoute and Site-to-Site VPN connections.
+    You may already have a virtual network in place with an existing Site-to-Site VPN connection or ExpressRoute connection. In this scenario if the gateway subnet prefix is /28 or longer (/29, /30, etc.), you have to delete the existing gateway. The [To configure coexisting connections for an already existing VNet](#add) section walks you through deleting the gateway, and then creating new ExpressRoute and Site-to-Site VPN connections.
 
     If you delete and recreate your gateway, you will have downtime for your cross-premises connections. However, your VMs and services will still be able to communicate out through the load balancer while you configure your gateway if they are configured to do so.