I'm not a musician, so I have no experience with this kind of thing. Can you tell us what issues come up in those circumstances?

Environmental conditions affect tone, tuning and the finish of the instrument. Temperature changes are also to be prevented. This is why the best place for a piano is against an inside wall and away from any sources of heat/cold and direct light.
Usually a safe range of humidity for an instrument ranges between 40%-60%. Try and avoid sudden changes in temperature or humidity. These changes will affect the moisture content of all the wooden parts, causing them to shrink or swell. This can cause the finish to chip or crack, the string tension to change, sluggish key and action parts.

High humidity can cause the wood to warp, while low humidity can cause cracking. As the wood loosens or tenses up, the strings will be impacted by it and so will the tuning.

I have lived overseas, in a very humid place, and my piano required tuning every 1 1/2-2 yrs. I now live in a dryer climate, and have only needed tuning once in 14 years. Also, when shipped, we packaged it with coverings that are used to ship instruments to Siberia. It went by sea, and shipped in the middle of winter. When it arrived, the tuning was still perfect. It was 6 years before a tune up was needed. It is a very good instrument, often referred to as a 'battlehorse' in Europe, but having lived in two different climates, I can still tell a great difference.

Hope this helps

lol I have a degree in Piano Performance. I just have to laugh about the length of time between tunings! Pianos need to be tuned at least 2x per year and possibly 3 or more times in a home setting. Professional situations tune before every performance. I couldn't image how terrible a 14 year tune must have sounded!!