Fun spoiler again sorry! Please remember the basic principle of Thai politics: appointed people appoint each other.
So, according to the Constitution (constitution which cannot be changed without approval of 2/3 of the appointed Senate), the next batch of Senators will be selected by panels and committees. These committees are dominated, by definition in the constitution, by appointed people (such as appointed heads of agencies, all appointed or vetted by the junta). Moreover, who will appoint the committee members? The EC (appointed or vetted by the Junta)
You may think, OK, let's be patient and wait for changes in the EC! But who will select or approve the new EC members? The Senate!
And around it goes!