Footprint charts are only for generalized reference and may not accurately indicate the true signal coverage. These computer generated estimations and simulations are based on full bandwidth and full power transponder operation to provide an acceptable level of reliability.
Typically there are footprint maps generated for each of the transmitted polarities. The footprints are usually different for each polarity. There are also many signal variables that are not modeled such as regional geomagnetic fields and actual transponder power, bandwidth, FEC ratio, etc. Often there are radiation irregularities that may produce signal hotspots outside of the estimated footprint.
A dish can only collect a signal that is present. If the footprint does not cover your region, there may not be enough signal to be received to amplify above the noise threshold and produce enough reliable data to decode. It won't matter the dish size or signal amplification, zero times 100 or even 1000 still equals zero.
With that said, if there is some signal present, it may be possible to increase it to be received via increasing the reflector size / efficiency and with optimized feedhorn / LNB low noise amplification and tuner sensitivity.
Several articles have been published about satellite DXing. It used to be much easier to receive an extremely weak or out of footprint analog signal as the snowy or unstable sync images still show up on the monitor even if the signal is at the noise threshold. With digital signals, the decoding will not happen unless a signal is a certain level above threshold and enough data is received over time to apply the FEC (error correction) to produce a viewable image.
There is an older Tele Satellite article that is a great read about a hobbyist using a gigantic dish and chilled LNB to receive the Austra/HotBird European footprint transponders in South America.
Out of footprint reception is not predictable and one would have to simply just give it a try using the largest / most efficient reflector, optimized feed and electronics available.
