Agree with Nicholas, keep track of what you do and then go for it. You won't know unless you test and if the product page has ranked highly before there is a good chance it will rank highly again if you de-optimize it's competing blog post page.

This could be due to a number of factors, however as of this morning (9/8/17) there is talk of a potential Google algorithm update- see more talk about it at https://www.seroundtable.com/google-search-algorithm-update-24433.html. This is just speculation but Google is showing a lot of SERP volatility in the last 24-36 hours.

Backlinks and Anchor Text. For example if you Google "click here" you will see alot of businesses that do not have "click here" on there website or meta title, but they have a lot of websites linking to them with the anchor text "click here", as an example.

This is a common thing we see especially when your meta title is "(Keyword Phrase) | (Company Name)". Keep in mind that the Yoast plugin only "strongly suggests" the Meta Title to show up in Google's SERPs, but Google can alter it, and often will if they think it is too keyword heavy or if they want to put the business name first instead of last.

I would test "Towing Services Alberta | Jack's Towing | 888-888-8888" if the client is ok with having their phone number in, this would put the business name in the middle of the title, which in our experience makes it less likely to be changed in SERPs. If the client does not want their phone number in SERPs you may have to experiment with it.

To speed up the testing process, use Google Search Console's Fetch & Render tool and re-index the page to see Google change the result in their SERPs alot faster (usually). Hope this helps and best of success!

I don't believe you can submit it too frequently. I would only do it when there is a change or once-a-month personally though.

You used to be able to do this in the YouMoz section of the Moz Blog at https://moz.com/ugc. However, the last post was almost a year ago, and according to a note on https://moz.com/posts/ugc_guidelines, the submission process is closed for the time being.

It you are able to edit Meta titles and meta descriptions on the website I would start there. If you are unable to even access this info on the website, I would focus on social signals and link building. So have a strong social media strategy and then work on gaining backlinks from authoritative websites. If this is a local company that wants to rank for "(your service) + (your city)" you can also focus on building quality business directory citations (Moz Local is great for this!). Best of success.

We agree with David above, if you are improving the title tags and keep them all unique and original from the other pages on your website doing a "Title Tag Cleanup" or going through and optimizing them should be a benefit. Some tips on Title Tags:

• Have The Keyword You Want To Rank For Be As Close To The Beginning As Possible
• Try to Make it short enough to were Google doesn't cut it off with "..." We use (https://www.portent.com/serp-preview-tool)
• Don't Duplicate Title Tags Across Pages, Try To Make Each One Unique
• Instead of Repeating A Keyword In a Title Try Using An "LSI Keyword" (For Example if you are attempting to rank for "marketing", use "marketing" once and then if desired, use a keyword like "advertising" or "media" etc.)

Hope this helps Luke and best of success!