There is another possibility; that it is two different PR people and the different phones are being used to differentiate the posts so that an analysis can more easily be done of which variety has the most effect. Perhaps a third party has already done this analysis.
Just because tweets or posts seem to be semi-literate or even badly spelled doesn’t mean they are not coming from a PR person; it may be that the PR agency thinks this will add “authenticity” in the minds of the target audience. GWBIII actually did become president, as did Reagan, and they didn’t do it on a platform of economic competence or educational attainment.
