Simple - when it's changed after the event!

We all assume that we are trading at the right hand edge and that rarely changes.
I knew the data feeds were always filtered (fat fingers,etc) but the subtle changes seem to have got way out of hand with Interactive Brokers.

I snapshot the chart throughout the day and then review my day at the end.
Today was a BAD day but do you see how different the chart and the indicators are - its not important what the indicators are.

The principle is that real time trading can be very different to sim and even trade review at eod - be warned.

Good trading!!

I noticed it many times in live trading rooms.

I usually see many different bars on a fast tick chart but never on time frame longer than 2 minutes .

Don't forget that graphics are just representing price as data.
The data is at the right time, right place, but electrical glitch ( bad Broker transmission speed and computing delay ) can make some ticks appear on the next bar or display that bar differently.

Now if you took a snapshot of your live chart and one from the replay, you can see bars based on pure data ( no glitch ) on the replay as it should have appeared ( no slippage ) and it should not be of concern.

Good trading!