Hi Enrico,
For 12.6 version, we didn't ship with web agent as the major change is mainly on policy server and CA Access gateway come with 64 bit installer.
Web agent already support 64 bit web server on 12.5x series so we are not included web agent in 12.6 release for this point of time. However, there might be possibility 12.6 will include web agent in future release.
In 12.6 platform matrix (https://support.ca.com/phpdocs/7/5262/5262_12_6_platform-support.pdf), you can find following in section 4.1 Policy Server and Agents Compatibility
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Any 6.x versions of Web Agents, Access Gateways (previously called Secure Proxy Server), ERP Agents, ASA Agents, and 5.x versions of ERP Agents that are not beyond their end-of-service date do not support IPv6 or FIPS Mode (and can only connect to 12.6 Policy Server in FIPS Compatibility Mode).
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This means 12.6 policy server is backward compatibility to web agent.
There is no plan to deprecate web agent in favor of CA AG.
Hope this helps.
Regards,
Kar Meng