Patch releases

Patch releases are designed to be small releases that address immediate problems within Mosaic. They are typically unplanned - any planned functionality would go into a major or minor release.
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When we have an issue that we consider may need patching, we run it through a patch process, which assesses the risk and impact of the issue. This process helps us make a decision about whether we need to issue a patch or not. We do this by exception, as it is not to anyone's benefit to have a large number of patches - every release takes extra resource from across the company, which we are then unable to use for other planned work.
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Once we have decided that we need a patch release, we carefully work to ensure that the patch is kept to a minimal size. If we allow other, less urgent, fixes to be included it increases the risk around the release - this may risk customers not being able to take it - or not being able to test it sufficiently. It is really important that we are stringent, as patch releases are usually something we would want all customers to be able to take.
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Where possible we try and ensure that a patch release is available as an EAR file, which significantly reduces the downtime/resource required to implement it. This is not always possible, but keeping the number of items included to a minimum does also help achieve this.
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When we are releasing a patch, we also regularly receive enquiries about patching back to earlier versions of the software. This is also discussed as part of the initial patch process and a decision is made for each as to whether this is necessary. Our default would be not to patch backwards - this is due to the amount of resource taken out by each separate release and the testing of it. The other significant reason against backward patching is that the functionality in each Mosaic release is different, so a fix that works in the latest version may not work or may need to function differently in a previous release - this could either cause more problems or result in an increase in development time.
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There are some occasions where an issue is serious enough to need to patch backwards, but this is very rare - generally due to the severity of the issue it would likely have already been found and fixed in the earlier release.
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We understand that it is frustrating having to wait for fixes, and that we can't just pop small fixes into a patch release, but I hope this helps to explain why that is. And equally, however small a fix might be, it still takes time, which we need to prioritise appropriately.