Another interpretation of "drew near": what Israel had traveled in three days, the scouts traveled in a day and a half, [and what the scouts traveled in a day and a half] Pharaoh traveled in a single day. Therefore it is said, "And Pharaoh drew near." "And the children of Israel lifted up [their eyes]" (Exodus 14:10) - since they had struck the scouts, they knew that in the end they would pursue after them. "And behold, Egypt was journeying after them" - it does not say "were journeying" but "was journeying after them," which teaches that they had all made themselves into squadron upon squadron, like one man. From here the kingdom learned to conduct itself in squadrons.
Pharaoh Outraced His Scouts and Egypt Marched as One Man
Yalkut Shimoni on Torah 230:19
דָּבָר אַחֵר, הִקְרִיב, מַה שֶׁהָלְכוּ יִשְׂרָאֵל בִּשְׁלשֶׁת יָמִים הָלְכוּ הָאוֹקְטוֹרִין בְּיוֹם וּמֶחֱצָה [וּמַה שֶׁהָלְכוּ הָאוֹקְטוֹרִין בְּיוֹם וּמֶחֱצָה] הָלַךְ פַּרְעֹה בְּיוֹם אֶחָד, לְכָךְ נֶאֱמַר וּפַרְעֹה הִקְרִיב. וַיִּשְׂאוּ בְנֵי יִשְׂרָאֵל. כֵּיוָן שֶׁהִכּוּ אֶת הָאוֹקְטוֹרִין הָיוּ יוֹדְעִין שֶׁסּוֹפָן לִרְדּוֹף אַחֲרֵיהֶן. וְהִנֵּה מִצְרַיִם נֹסֵעַ אַחֲרֵיהֶם. נוֹסְעִים אֵינוֹ אוֹמֵר אֶלָּא נוֹסֵעַ אַחֲרֵיהֶם, מְלַמֵּד שֶׁעָשׂוּ כֻּלָּן טוּרְמִיּוֹת טוּרְמִיּוֹת כְּאִישׁ אֶחָד. מִכָּאן לָמְדָה מַלְכוּת לִהְיוֹת מִתְנַהֶגֶת טוּרְמִיּוֹת.