How to publish nodes 3 times a day? I have a list of unpublished nodes, created with the Views module. I would like a task to be run 3 times a day, at specified times. Every time the task  runs, only one of the nodes on the list should be published. How can I do this?
Steps I have tried
Scheduler
The Scheduler module requires you to specify the exact time you want the node to be published. This makes it complicated, as I would have to work out when each node is supposed to be published.
Views Bulk Operations + Rules + Rules Scheduler
With the Views Bulk Operations module, you can create a list of Nodes that are exposed to the Rules module. Rules can then act on the list and publish the node on the list. You can tell Rules to only publish a specific number of nodes.
This works perfectly. Except, it doesn't seem possible to schedule the Rule to run 3 times a day.
You can link the Rule to the main site Cron job, but this doesn't seem very precise as the Cron job could run more than 3 times.
There is a Rules Scheduler module (a sub-module of Rules), but it doesn't look like you can use this a Rules condition. There also doesn't seem to be a way to specify the running time.
Job Scheduler
This lets you set a time, but it doesn't seem to integrate with Rules or Views.
Using modules VBO, Rules and Rules Scheduler

About your approach using modules Views Bulk Operations (VBO), Rules and Rules scheduler (submodule of Rules), for which you wrote "it doesn't seem possible to schedule the Rule to run 3 times a day.": that appears to me "a" valid approach.

What you actually need to do is a minor variation of what is explained in the tutorial Hourly tasks using rules scheduler: in your case you should use an offset of 8 hours (instead of just 1).

And as explained also in that tutorial: Initially execute the component manually. (from then on every other 8 hours the rule will be executed again).

Using modules Rules and Rules Once per Day

There is a fairly new module related to rules, i.e. the "Rules Once per Day" module. Here is how it works (as per the comment in issue 2495775, from the module owner):


You specify a trigger hour on the administration settings page for this module.
The Rule trigger will then run when cron tasks are first run after the start of that hour. The actual run time will depend on your cron task timings.


The way I understand/Read this (haven't experimented with it yet though) is like so:


The "Event" will only be triggered when a cron job is run.
And that event will only be triggered 1 time / day, i.e. "next time cron runs after the trigger hour has passed".


So by creating 3 similar rules, you could have 1 of them run around (say) 6 pm, another one around 2 pm and the ast one at 10 pm.

PS: I'm assuming this question is about D7.