The Lilywhites have spent the majority of the campaign in the upper reaches of the Championship and were top for a brief spell in November.
They were sixth when the season was halted in March with 37 games played.
Johnson says a great deal of hard work has gone into being in the play-off chase and wants to have the chance to complete the season, however that might turn out.
“It’s been tough to get into the top six and we have worked hard to get there,” said Johnson.
“We know it’s not finished yet and hopefully we can resume at some point and kick on again.
“The Championship is a relentless division with a lot of Saturday/Tuesday games and you do work hard to try and get to where you want to be.
“At one point this season we were top of the table and were second for a time too.
“That is football, things change quickly.
“We know we are in such a good position, it is in our hands.
“When we do get the chance to resume, hopefully we can keep hold of that top-six spot.
“As a group of players we know what we are capable of delivering.
“We have a really good bunch of lads here who get the best out of one another.”
Johnson thinks lessons can learned from the last couple of seasons when PNE were on the edge of the race for the play-offs but did not make it.
Two seasons ago they finished seventh in the table, a strong late run carrying them close.
Last year they closed to within goal difference of the top six in March only to have a dreadful finish which saw them drop away to 14th.
Said Johnson: “We know what it will take to get over the line, we have tweaked things from previous seasons.
“Luckily for us, it has been working and hopefully at some point we can get back out there to show that again.”
Johnson, 27, went into the enforced break as North End’s leading scorer in the league with 11 goals.
Six of those came from the penalty spot, with him scoring in the 3-1 defeat to QPR on March 7 which was the final game before the season was suspended.
In his five years at North End he has scored 42 goals in all competitions.