The simplest solution is to reduce the mailings to those with active subscriptions or recent transactions, but the best solution is an opt-in system that requires that the email recipients opt in. I believe that I mentioned this to you in a previous email. An opt in system would be a fairly significant addition to the software system.
Updating PHP is also a major task, even bigger than the email issue. The reason is that PHP decided that it was going to eliminate the old programming interface (called an API) to the MySLQ database several years ago and replace it with a new interface (API). They set PHP up to give warnings when using the old API at that time so that people had several years to upgrade their code before it became mandatory (i.e. it generated errors). The old interface is used in the Growing Child software (all of it, including the web software and the back office software) probably over 1000 times in virtually every code module (and there are over 100, probably over 200 code modules). The change to the new interface is fairly easy to do, but each change could result in a small typo that makes the code non-functional, so every change has to be tested. The testing will take several fold more effort than the effort needed to edit the code to switch to the new interface. Doing the testing requires fairly highly developed knowledge of the system as well as some expertise with system (code) development on an isolated instance (sub-system). When I was working on the Growing Child system, a fully isolate development system was needed for testing new code before putting it into production, but my work ended before I was able to work on creating such a development system. If such a system existed, it would be much easier to test the newly modified code. There are several ways to create such a system, some easier than others. One is to create it on the same server as the production system using subdomains that are not available to the public. While that takes the most effort, it has the advantage of testing the code in the correct operating environment. Technically, this may not be possible, as the PHP version upgrade needed (and needing testing before it being put into production) may have to be done on all domains, including the development subdomain, at the same time (since it is a server function)
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